Voyager Has Left The Solar System (This Time For Real!)

A NASA image of one of the Voyager space probes, launched in 1977 to study the outer solar system and eventually interstellar space.

NASAGetty Images

Originally published on September 12, 2013 5:31 pm

Stop us if you've heard this one: A spacecraft flies out of the solar system ...

Yes, the planetary probe Voyager 1, launched in the era of Jimmy Carter and bell-bottoms, has finally left the room, so to speak, years after completing its primary mission: a "grand tour" of the gas giants Jupiter and Saturn (twin Voyager 2 also visited Uranus and Neptune).

That's the first of many stories we've done over the years anticipating Voyager's arrival at the mysterious boundary called the heliopause, a region of space where the solar wind dies out and interstellar space begins.

The problem is, that "it's not that clear because there's no signpost telling you that you're now leaving the solar system," Arik Posner, Voyager's program scientist, told me in an interview last year.

Signpost or no signpost, Posner and others now say (and are pretty confident this time) that Voyager crossed over the boundary (drumroll ...) more than a year ago — Aug. 25, 2012, to be precise.